Gear pump movable elements having a plurality of sealing forces



Feb. 25, 1969 NQELL ETAL 3,429,270

HAVING A PLURALITY GEAR PUMP MOVABLE ELE TS OF SEAL FORCES Filed Aug. 9, 1967 Sheet Of 5 4/ iii) Jfl GODW/N L. NOELL AEROY A. D/FFQQD 5y 2 4.6411 w. W

3,429,270 GEAR PUMP MOVABLE ELEMENTS HAVING A PLURALITY F SEALING FORCES Godwin L. Noell, Middletown, and Le Roy A. Ditford, Simshury, Conn., assignors to Chandler Evans Inc., West Hartford, Conn., a corporation of Delaware Filed Aug. 9, 1967, Ser. No. 659,398 U.S. Cl. 103--126 16 Claims Int. Cl. F04c 1/14 ABSTRACT OF THE DISCLOSURE Background of the invention This invention pertains to gear pumps capable of pumping a fluid containing highly abrasive contaminants wherein the pump comprises a housing with a pair of meshed toothed gears disposed therein having separate movable elements adjacent the pump outlet engaging the periphery of each gear in a one-to-one relationship to maintain continuous peripheral sealing engagement during independent movement of the gears. The construction of a gear pump having separate movable elements trackably engaging the periphery of the driver gear and the driven gear respectively is described in US. patent application of inventors Noell, Cygnor and Sundberg entitled, Gear Pump, filed on even date herewith and assigned to the same assignee as the instant application. Reference may be had to said application for a detailed description and explanation of the construction and operation of a gear pump having a driver gear and a driven gear with separate trackable pivotable movable elements urged into engagement with the periphery of the driver gear and driven gear respectively to maintain continuous peripherial sealing engagement during independent movement of the gears.

The pump construction described in US. patent application of inventors Noell, Cygnor and Sundberg entitled Gear Pump filed on even date herewith utilizes separate movable elements that are pivotably disposed in relation to a loading device such that the resulting vectored forces are transmitted from the loading device to each separate element through a single pivotable contact point. It has been found that under certain pump operating conditions pivotable movable elements constructed in accordance with the teachings of this invention may be cyclically lifted several thousands of an inch on the outboard low pressure extremity at the point where the gear teeth enter the movable element, thereby resulting in a marked decrease in volumetric efficiency.

The cyclic lifting phenomena experienced by the outer extremity of the pivotable movable element can best be described by reference to FIGURE 9, wherein the structure to the right of the plane of symmetry graphically represents the most severe loading conditions that the movable element can experience. The structure to the left of the plane of symmetry is a mirror image of that shown on the right. Lines 101 through 106, both inclusive, each graphically represents a tooth on the gear shown generally at 7. Similarly, lines 107 through 110, both inclusive, graphically represent a tooth on the gear shown generally Staes i atent O F at 6. As gear 7 rotates about axis 11 with respect to movable element 100, at one instant in time gear tooth 101 moves off the engaging arcuate surface of movable element at this particular instant in time, the volume of fluid confined between teeth 101 and 102 is at pump inlet pressure. Tooth 101 has become disengaged from movable element 100, and the surface of element 100 adjacent the plane of symmetry is subjected to discharge pressure thus creating a force that tends to pivot element 100 about tooth 102. This is a transient condition that exists at the instant tooth 101 moves out of engagement wtih member 100 and is due to the pressure response caused by the compressibility of the fluid being pumped. The force tending to pivot element 100 about tooth 102 is represented analytically in FIGURE 9 by the couple F R An additional force F representing the compo nent of force transverse the F force and caused by the action of discharge pressure on pivotable element 100 causes a moment about R Thus, it can be seen that when the couple F R and F R simultaneously act on element 100 without a compensating reacting moment, as is the case with a single pivotable protuberance, as disclosed in the aforementioned application of inventors Noell, Cygnor and Sundberg, the outboard extremity indicated generally at 111 tends to lift off and disengage itself from the periphery of gear teeth 103, 104 and 105. A reaction must be provided at the pivot point 112 of element 100 to compensate for the moments F R and FQRZ. The inclusion of a second loading point 113 as shown in the instant case provides for a compensating moment F acting through pivot point 112 that permits the extremity 111 to remain in engagement with the periphery of teeth 103, 104 and 105 and thus preclude the cyclic lifting of the outer extremity 111 of the pivotable movable element 100. The cyclic force moments are minimized when the sealing point is located at the distance a/ 2 as shown in FIGURE 9. The distance a/ 2 represents one-half the projected length of one tooth cavity measured from the point of disengagement of the tooth from the movable element 100. The lengths b, c and d are sized to distribute the reaction forces over as many teeth as possible and still provide adequate sealing and pump operation. It is to be noted that the hydraulic force designated F acts on element 100 when discharge pressure is present in the cavity formed by gear teeth 101 and 102.

It is apparent that the portions of the gears subjected to discharge pressure should be minimized in order to minimize the gear shaft journal bearing loads. It is clearly apparent if the pivot contact points 112 as shown in FIG- URE 9 were moved outboard relative to the plane of symmetry in an effort to produce a moment that would counterbalance the moment F tending to tip the extremity 111 of element 100, an undesirable increase in journal bearing load would result since a larger portion of the element 100 would he exposed to pump discharge pressure due to the fact the pivot contacting surface 112 also acts as the high pressure sealing surface. Thus it is necessary to provide a second independent point of force application such as protuberance 113 for example, as shown in FIGURE 9, while maintaining the original pivot sealing point 112 in its predetermined optimum geometric position. Thus whatever form may be used, a second independent load outboard of the pivot sealing point must be applied to prevent the lifting of the outer extremity of the pivotably movable element while still maintaining minimum shaft journal loads.

It has been found that the cyclic forces tending to lift the outer extremity of the pivotably movable element from engagement with the mating periphery of the gear teeth can be controlled by providing an independent load outboard of the pivot contact point, said load producing a compensating reaction moment that cancels the moment tending to lift the outer extremity of the pivotably movable element from engagement with the periphery of the gear teeth.

Summary of the invention This invention pertains to a gear pump that can pump fluid containing a highly abrasive contaminant and continue to maintain a high volumetric efficiency after the pump has been run for a protracted period of time. The gear pump of the kind specified utilizes separate pivotably movable sealing elements positioned adjacent the pump outlet. One of the pivotably movable elements engages the periphery of at least two teeth of one gear, and the other pivotably movable element engages the periphery of at least two teeth of the second gear. Both pivotably movable elements are independently loaded by discharge pressure and mechanical biasing means to thereby generate a series of independent forces such that at least two independent forces are applied to each pivotably movable element to thereby continually urge both pivotably movable elements into continual peripheral tooth sealing engagement under all operating conditions.

Accordingly, it is an object of the present invention to provide an improved gear pump having pivotably movable elements adjacent the pump outlet for pumping contaminant fluid containing a highly abrasive contaminant that will maintain the outer extremities of the pivotably movable elements in engagement with the periphery of the mating gear teeth under all conditions of pump operation.

Another object of this invention is to provide a gear type pump wherein separate pivotably movable elements are positioned adjacent the pump outlet and each element is held in peripheral sealing engagement with the periphery of one of the gears respectively by the application of an independent force to each element outboard of the point of pivotable sealing engagement.

A specific object of this invention is to provide a gear pump having separate pivotably movable elements for each gear located adjacent the pump outlet, each element engaging the periphery of its respective gear with each element held in position by two separate forces, one of said forces being applied to each element outboard of the pivot point such that the outboard extremities of both of said pivotably movable elements are maintained in stable sealing engagement with the periphery of the teeth of their respective gears.

Another object of this invention is to provide a gear pump having separate pivotably movable elements for each gear located adjacent the pump outlet with each pivotably movable element being so configured that two independent means for applying a force to each element are provided such that one force acts through the pivot contact protuberance which also acts as the high pressure sealing surface, and a second force is applied outboard of the sealing point to thereby expose the minimum portion of the wear block to discharge pressure and simultaneously provide a loading configuration that will maintain the outboard extremity of the pivotably movable element in continuous sealing engagement with the periphery of the mating gear teeth under all conditions of operation.

Many other advantages and features of this invention will become manifest to those well versed in the art upon making reference to the description which follows.

Description of the drawings The following is a brief description of the drawings accompanying the detailed description of the instant invention.

FIGURE 1 is a front view of a first form of gear pump incorporating the present invention.

FIGURE 2 is a sectional view along the line 22.

FIGURE 3 is a sectional view along the line 3-3.

FIGURE 4 is a cross-sectional View along the line 44.

FIGURE 5 is a detailed cross-sectional view in accord with this invention having a first alternate form of movable peripheral sealing assembly.

FIGURE 6 is a detailed cross-sectional view in accord with this invention having a second alternate form of movable peripheral sealing assembly.

FIGURE 7 is a detailed cross-sectional view in accord with this invention having a third alternate form of a movable peripheral sealing assembly.

FIGURE 8 is a detailed cross-sectional view in accord with this invention having a third alternate form of movable peripheral sealing assembly.

FIGURE 9 is a fragmentary section of a gear pump showing a graphical representation of the instantaneous application of the various loading forces to each pivotably movable element.

Referring now to the drawings in the following general description, like parts are designated throughout by like numerals for all forms shown.

Referring to the example shown in FIGURES l, 2, 3 and 4, there is provided a pump having a housing 1 defining therein a cavity 2 and a pair of end plates 3 and 4 positioned on opposite sides of housing 1 and secured in fluid tight relation to said housing by a plurality of bolts 5. Rotatably mounted about axes of rotation 11 and 12 in cavity 2 of housing 1 are a pair of intermeshing gears 6 and 7 engaging one another at an area of intermesh indicated generally at 8. Shaft 9 drives gear 6 through a key (not shown). Shaft 10 is keyed to driven gear 7 such that shaft 10 and gear 7 rotate in unison responsive to rotative movement of driver gear 6. Shafts 9 and 10 are journaled in bearings 13, 14, 15 and 16 respectively with a close running fit such that axes of rotation 11 and 12 are maintained substantially parallel. Gears 6 and 7 are disposed in cavity 2 such that an outlet 17 is formed on one side of the intermesh 8 and an outlet 18 is formed on the opposite side of the intermesh 8 so that the rotary fluid displacement means comprising the intermeshing gears 6 and 7 will operate to move the fluid medium acted upon by the pump from the inlet 17 to the outlet 18. As is clearly indicated in FIGURES 2 and 4, the outer diameter of the gears 6 and 7 at the tips or periphery of the gear teeth are disposed in relation to the peripheral wall of cavity 2 adjacent the pump inlet such that there is a pronounced clearance between the periphery of each of the gear teeth and the adjacent cavity wall. This clearance is provided to reduce the possibility of cavitation of the pump inlet when the pump is operated at high speed. In order to provide peripheral tooth sealing adjacent the pump outlet 18 there is provided in accordance with the teachings of this invention a novel movable peripheral sealing means engaging the periphery of both the driver gear and the driven gear. In this particular embodiment the pivotable movable sealing means takes the form of first and second pivotably movable members 119 and 120 having elongated depressions 124 and 125 that pivotably engage protuberances 122 and 121 respectively of loading element 123.

Peripheral sealing elements 119 and 120 are continuously urged into peripheral sealing engagement with at least two teeth in the areas 27 and 28 of gears 6 and 7 respectively by springs 128 and 129 received by depressions 130 and 131 respectively of sealing spacer 142. Also springs 128 and 129 urge protuberances 122 and 121 of loading element 123 into engagement with depressions 124 and 125 to thereby provide the initial fluid sealing between said protuberances and their mating depressions until the buildup of fluid pressure in chamber 53. Discharge pressure is communicated from discharge chamber 53 via interconnected passageway 132 to chamber 133 to provide a fluid pressure responsive force supplemental to that provided by springs 128 and 129. Said combined fluid pressure responsive and spring force is transmitted through pivotable protuberances 122 and 121 to elements 119 and 120 to generate first vectored forces through elements 119 and 120 that are continuously positioned in substantial proximity respectively to axes of rotation 12 and 1 1 such that moveable elements 119 and 120 are continuously positioned in peripheral tooth sealing engagement with at least two teeth of gears 6 and 7 respectively.

Movable elements 119 and 120 contain cavities 134 and 135 respectively. Integral projections 136 and 137 of loading element 123 sealingly slideably engage cavities 134 and 135 respectively to form variable volume chambers 138 and 139. Discharge pressure is communicated from variable volume pressure chamber 133 to variable volume pressure chambers 138 and 139 via interconnecting passageways 140 and 141 respectively. The discharge pressure communicated to chambers 138 and 139 provides second independent forces to elements 119 and 120. The forces generated by pressure chambers 138 and 139 are positioned outboard of the respective pivot points 122 and 121 and generate independent vectored forces positioned adjacent the outboard extremities of movable elements 119 and 120 such that the outboard extremities of sealing elements 119 and 120 are continuously maintained in sealing engagement with the mating gear tooth periphery under all pump operating conditions.

Side members and 36 are positioned intermediate the lateral faces 37 and 144 of gear 6, the lateral faces 38 and 143 of gear 7, and the side surfaces 39 and 40 of end plates 3 and 4 respectively. Seal 41 is located in recess 42 of end plate 3 and positioned intermediate side plate 35 and end plate 3 to form cavity 43. Seal 44 is positioned in recess 45 intermediate side plate 35 and end plate 3 to form cavity 46. Similarly seals 47 and 48 are positioned intermediate end plate 4 and side plate 36 to form chambers 49 and 50. Fluid at discharge pressure is directed through passageways 51 and 52 into chambers 43 and 49 respectively and thence via interconnecting passageway (not shown) to chambers 46 and Side plates 35 and 36 responsive to discharge pressure contained in chambers 43, 46, 49 and 50 are urged into sealing engagement with the lateral faces of gears 6 and 7 and the end faces of elements 119 and 120' to form a discharge pocket 53 bounded by the intermesh 8 of the teeth of the two gears, peripheral sealing contact areas 27 and 28 of the periphery of the teeth of gear 6 and movable element 119 and the periphery of the teeth of gear 7 and moveable element 120. It has been found that the peripheral sealing between the periphery of the gear teeth and the mating arcuate surfaces of the movable elements 119 and 120 is the critical leakage path with respect to the operation of a gear pump when pumping a fluid medium containing highly abrasive contaminants. This critical peripheral sealing engagement is represented by areas 27 and 28 of FIGURE 4. Accordingly, it is to be understood that the embodiment shown utilizing the two side plates 35 and 36 is representative of but one form of providing the fluid sealing discharge pocket 53. It has been found that any form of pressure loaded side plate that will urge the lateral surfaces of the gears and the end surfaces of the movable elements into the fiuid sealing engagement so as to form the fluidly sealed discharge pocket 53 will perform satisfactorily when pumping highly abrasive contaminant fluids. Accordingly, side plate mechanisms having surfaces in contact with 100% of the lateral surfaces of the pump gears, as exemplified by Roth, Patent No. 2,420,622; intermediate housing pressure loading, as exemplified by Gordon, Patent No. 3,292,550; selective side plate loading, as exemplified by Banker, Patent No. 2,742,862; or free floating side plates, as exemplified by Trautman, Patent No. 2,996,999, may all be used with equally satisfactory results so long as the side plate or plates urge the lateral surfaces of the gears and the end surfaces of the movable elements into sealing engagement with the side plates or the mating surfaces of the end plates such that a fluidly sealable discharge pocket 53 is formed.

FIGURE 5 shows an alternate movable peripheral seal means for obtaining the necessary continuous peripheral tooth sealing engagement adjacent the pump outlet and simultaneously applying a second independent force to each pivotable movable element that will maintain the outer extremities of the pivotable elements in engagement with the periphery of the mating gear teeth under all conditions of pump operation. The alternate construction shown in FIGURE 5 comprises pivotable movable sealing elements and 146 having elongated depressions 151 and 152 that pivotably engage integral protuberances 153 and 154 respectively of loading piston 150. Peripheral sealing elements 145 and 146 are continuously urged into peripheral sealing engagement with at least two teeth in the areas 27 and 28 of gears 6 and 7 respectively by spring 156 received by depression 178 of sealing spacer 149. Also spring 156 initially urges protuberances 153 and 154 into fluid sealing engagement with mating depressions 151 and 152 until the buildup of pressure in discharge chamber 53. Discharge pressure is communicated from discharge chamber 53 via interconnected passage to variable volume chamber 177 to thereby provide a discharge pressure responsive force supplemental to that provided by spring 156. Said combined fluid and spring force is transmitted through pivotable protuberances 153 and 154 to elements 145 and 146 to generate first vectored forces, through elements 145 and 146, that are continuously positioned in substantial proximity respectively to axes of rotation 12 and 11 such that movable elements 145 and 146 are continuously positioned in peripheral tooth sealing engagement with at least two teeth of gears 6 and 7 respectively.

The housing 1 is provided with a pair of cavities 179 and 180 adjacent to and positioned on opposite sides of the pump outlet outboard of pivot sealing points 151 and 152 respectively. Cavities 179 and 180 are cantedly positioned on opposite sides of outlet 18 and slideably sealing engage movable elements 147 and 148 respectively to form variable volume chambers 159 and therebetween. Pivotably movable sealing elements 145 and 146 are continuously urged into peripheral sealing engagement at their outer extremities with the periphery of the gear teeth of gears 6 and 7 respectively by springs 157 and 158 received by depressions 181 and 182 of slideably movable elements 147 and 148 respectively. Discharge pressure is communicated frorn variable volume chamber 177 to variable volume chambers 159 and 160 via interconnecting passageways not shown. Discharge pressure communicated to chambers 159 and 160 provides second independent forces to elements 145 and 146. The forces generated by pressure chambers 159 and 160 are positioned outboard of the respective pivot points 151 and 152 and generate independent vectored forces positioned adjacent the outboard extremities of pivotable movable elements 145 and 146 such that the outboard extremities of elements 145 and 146 are continuously maintained in sealing engagement with the mating gear tooth periphery under all pump operating conditions.

FIGURE 6 discloses still another alternate arrangement wherein the two pivotably movable peripheral sealing elements 161 and 162 pivotably engage protuberances 177 and 183 of loading element 163. Pivotably movable elements 161 and 162 have elongated recesses 184 and 185 that pivotably engage protuberances 177 and 183 of loading piston 163. Protuberances 177 and 183 have spaced apart pivotable contacting surfaces 186, 187, and 188, 189 respectively.

Pivotable sealing elements 161 and 162 are continuously urged into peripheral sealing engagement with at least two teeth in the areas 27 and 28 of gears 6 and 7 respectively by spring received in depression of loading element 163. Discharge pressure is communicated from discharge chamber 53 via interconnected passageway 166 to variable volume chamber 190 to provide a discharge pressure responsive force supplemental to that provided by spring 165. The combined pressure responsive and spring force is transmitted through contact points 186 and 188 of pivotable protuberances 177 and 183 to elements 161 and 162 to generate first vectored forces through elements 161 and 162 that are continuously positioned in substantial proximity respective to axes of rotation 12 and 11 such that movable elements 161 and 162 are continuously positioned in peripheral tooth sealing engagement with at least two teeth of gears 6 and 7 respectively.

Loading element 163 contains cavities 191 and 192 positioned on opposite sides of outlet 18 and substantially transverse the plane of symmetry. Movable elements 169 and 170 are sealably slideably positioned in cavities 191 and 192 respectively and engage elongated integral protuberances 167 and 168 of pivotable movable elements 161 and 162 respectively. Pivotable movable elements 161 and 162 are continuously urged into peripheral sealing engagement with the mating gear teeth of gears 6 and 7 respectively by springs 171 and 172 positioned intermediate movable elements 169 and 170 and the end wall of cavities 191 and 192 respectively. Also springs 171 and 172 initially urge the surfaces of recesses 184 and 185 into fluid sealing engagement with mating protuberances 187 and 189 until the buildup of pressure in chamber 53. Discharge pressure is communicated from chamber 53 to variable volume chambers 193 and 194 via interconnecting passageways 173 and 174 respectively to provide a pressure responsive force to movable elements 169 and 170 to supplement that provided by springs 171 and 172. Said combined pressure responsive and spring force is transmitted through elongated protuberances 167 and 168 via pivot points 187 and 189 to generate second independent forces to elements 161 and 162. The forces generated by pressure chambers 193 and 194 are positioned outboard the respective pivot points 177 and 178 and generate independent vectored forces positioned adjacent the outboard extremities of pivotable movable elements 161 and 162 such that the outboard extremities of said elements are continuously maintained in sealing engagement with the mating gear tooth periphery under all pump operating conditions.

FIGURE 7 discloses still another alternate arrangement wherein discharge pressure is communicated via passageway 260 from discharge chamber 53 to variable volume 206 of movable loading element 196 to thereby generate a force that is communicated through pivotable protuberances 197 and 199 to abutting surfaces 207 and 209 of recesses 225 and 226 respectively. Said force is then transmitted from surfaces 207 and 209 of pivotable movable elements 193 and 194 respectively to thereby urge elements 193 and 194 into peripheral sealing engagement with gears 6 and 7 respectively. Said loading means 196 has elongated pivots 198 and 200 positioned on opposite sides of said plane of symmetry, said elongated pivots being spaced apart from loading protuberances 197 and 1-99 positioned on each side of said plane of symmetry and engaging abutting surfaces 208 and 210* of recesses 225 and 226 of pivotable movable elements 193 and 194 respectively. Pivotable sealing elements 193 and 194 are continuously urged into peripheral sealing engagement in the areas 27 and 28 of the gears 6 and 7 respectively by spring 205 received in depression 206 of spacer 195. The force provided by spring 205 is supplemental to the pressure responsive force of variable volume chamber 206 to provide a combined pressure responsive and spring force that is transmitted through load points 197 and 199 to abutting surfaces 207 and 209 to thus generate first vectored forces through elements 193 and 194 that are continuously positioned in substantial proximity to axes of rotation 12 and 11 respectively. Springs 203 and 204 are received in cavities 201 and 202 of loading element 196. Said cavities 201 and 202 are positioned on opposite sides of and are substantially transverse to said plane of symmetry. Said springs 203 and 204 engage elongated protuberances 227 and 228 respectively of elements 193 and 194 to initially provide sealing between pivots 198 and 200 and abutting surfaces 208 and 210 prior to the buildup of fiuid pressure in chamber 53. Also second independent moments are generated about pivots 198 and 200 and abutting surfaces 208 and 210 such that the outer extremities of movable elements 193 and 194 are maintained in continuous sealing engagement with the periphery of the mating gear teeth.

FIGURE 8 discloses still another alternate arrangement wherein pivotably movable peripheral sealing elements 211 and 212 pivotably engage protuberances 217 and 218 of loading element 213; said loading element 213 having pivot protuberances 217 and 218 positioned on opposite sides of said plane of symmetry and spaced apart spherical loading protuberances 219 and 220 positioned on each side of said plane of symmetry and engaging abutting surfaces 229 and 230 of recesses 231 and 232 of movable elements 211 and 212 respectively.

Pivota'ble sealing elements 211 and 212 are continuously urged into peripheral sealing engagement in the areas 27 and 28 of gears 6 and 7 respectively by spring 216- received in depression 215 of spacer 214. Discharge pressure is communicated from discharge chamber 53- via interconnected passageway 234 to variable volume chamber 235 to provide a discharge pressure responsive force supplea mental to that provided by spring 216. The combined pressure responsive and spring force is transmitted through spherical contact points 219 and 220 to abutting surfaces 229 and 230 respectively of elements 211 and 212 to generate first vectored forces through elements 211 and 212 such that said vectored forces are continuously positioned in substantial proximity respective to axes of rotation 12 and 11 to thereby continuously position movable elements 211 and 212 into peripherial tooth sealing engagement with gears 6 and 7 respectively.

Loading element 213 contains a plurality of cavities shown generally at 221 and 222 positioned on opposite sides and transverse to said plane of symmetry. A plurality of springs shown generally at 223 and 224 are received in the respective cavities 221 and 222 and engage elongated protuberances 236 and 237 of elements 211 and 212 respectively to generate second independent moments about pivot points 217 and 218 such that the outer extremities of movable elements 211 and 212 are maintained in continuous sealing engagement with the periphery of their mating gear teeth. Also springs 223 and 224 urge the surfaces of elements 211 and 212 that engage mating protuberances 217 and 218 into initial fluid sealing engagement with said protuberances 217 and 218 until pressure is built up in chamber 53.

What we claim is:

1. A gear pump comprising a housing and enclosing a chamber, a pair of intermeshing gears supported on parallel axes for rotation in said chamber, movable pressure loaded peripheral sealing means for said gears, at least one pressure loaded side plate urged into engagement with the lateral faces of said gears and said peripheral sealing means to sealingly divide said chamber into a high pressure portion and a low pressure portion, said peripheral sealing means having a first articulated element having a first resultant vectored force impressed thereon, said first force continuously positioned in substantial proximity to the axis of rotation of said first gear, and a second articulated element having a second resultant vectored force impressed thereon, said second force continuously positioned in substantial proximity to the axis of rotation of said second gear, additional means generating a plurality of separate forces for turning said first element and said second element about their respective articulation points, loading means independent of pressure continuously forcing the arcuate surfaces of said first and second elements into peripheral tooth sealing engagement.

2. A gear pump comprising a housing having a bore and means providing a closure for each end of said housing, a driver gear and a driven gear, each of said gears having an axis of rotation, said gears disposed in said bore and journaled in said housing such that said axes of rotation are parallel, a plane of symmetry located intermediate and equidistant said axes of rotation and positioned trans verse a plane containing said axes of rotation, said gears having an intermesh intermediate said axis of rotation, an inlet on one side of said intermesh and an outlet on the opposite side of said intermesh, movable peripheral sealing means positioned adjacent said outlet, at least one pressure loaded side plate urged into engagement with the lateral surfaces of said gears and said movable peripheral sealing means to sealingly enclose a high pressure discharge chamber, said movable sealing means having a first pivotable element engaging the periphery of said driver gear, a second pivotable element engaging the periphery of said driven gear, loading means having an elongated protuberance on each side of said plane of symmetry said protuberances pivotably engaging mating recesses in said first and second elements respectively, said loading means having a third and fourth protuberance positioned outboard said first and second protuberances respectively, a cavity located in said first element and said second element receiving said third and fourth protuberances respectively to thereby form a pair of chambers, discharge pressure communicated to said chambers to generate moments about each of said protuberances such that the outboard extremities of said first element and second element with respect to said plane of symmetry are maintained in stable sealing engagement with the tooth periphery of said gears.

3. A gear pump, as defined in claim 2, wherein said movable sealing means is continuously urged by spring means toward said gears for peripheral sealing engagement therewith.

4. A gear pump, as defined in claim 3, wherein discharge pressure urges the pivotable protuberances of said loading means into pivotable engagement with said first and second elements to produce a line contact high pressure fluid seal between said pivot protuberances and the engaging surfaces of said first and second elements, and simultaneously generates first and second vectored forces continuously positioned in substantial proximity to the respective axes of rotation of said gears.

5. A gear pump comprising a housing having a bore and means providing a closure for each end of said housing, a driver gear and a driven gear, each of said gears having an axis of rotation, said gears disposed in said bore and journaled in said housing such that said axes of rotation are parallel, a plane of symmetry located intermediate and equidistant said axes of rotation and positioned transverse a plane containing said axes of rotation, said gears having an intermesh intermediate said axis of rotation, an inlet on one side of said intermesh, and an outlet on the opposite side of said intermesh, movable peripheral sealing means positioned adjacent said outlet, at least one pressure loaded sideplate urged into engagement with the lateral surfaces of said gears and said movable peripheral sealing means to sealingly enclose a high pressure discharge chamber, said movable sealing means having a first pivotable element engaging the periphery of said driver gear, a second pivotable element engaging the periphery of said driven gear, loading means having an integral elongated protuberance on each side of said plane of symmetry, said protuberances engaging mating recesses in said first and second elements respectively, said housing having a cavity positioned on each side of said plane of symmetry, a pair of pistons received by said housing cavities to form a pair of chambers, discharge pressure communicated to said chambers, said pistons engaging the outer extremities of said first and second elements respectively in relation to said plane of symmetry, discharge pressure communicated to said chambers to thereby generate moments about each of said protuberances such that said outboard extremities of said first and second elements are maintained in continuous sealing engagement with the periphery of said gear teeth.

6. A gear pump, as defined in claim 5, wherein said movable sealing means is continuously urged by spring means toward said gears for peripheral sealing engagement therewith.

7. A gear pump, as defined in claim 6, wherein discharge pressure urges the pivotable protuberances of said loading means into pivotable engagement with said first and second elements to produce a line contact high pressure fluid seal between said pivot protuberances and the engaging surfaces of said first and second elements and simultaneously generates first and second vectored forces continuously positioned in substantial proximity to the respective axes of rotation of said gears.

8. A gear pump comprising a housing having a bore and means providing a closure for each end of said housing, a driver gear and a driven gear, each of said gears having an axis of rotation, said gears disposed in said bore and journaled in said housing such that said axes of rotation are parallel, a plane of symmetry located intermediate and equidistant said axes of rotation and positioned transverse a plane containing said axes of rotation, said gears having an intermesh intermediate said axis of rotation, an inlet on one side of said intermesh, and an outlet on the opposite side of said intermesh, movable peripheral sealing means positioned adjacent said outlet, at least one pressure loaded sideplate urged into engagement with the lateral surfaces of said gears and said movable peripheral sealing means to sealingly enclose a high pressure discharge chamber, said movable sealing means having a first pivotable element engaging the periphery of said driver gear, a second pivotable element engaging the periphery of said driven gear, loading means having an integral elongated protuberance on each side of said plane of symmetry, said protuberances engaging mating recesses in said first and second elements respectively, said loading means having a cavity positioned in each side of said plane of symmetry, a piston received by each of said loading means cavities to form a pair of chambers, discharge pressure communicated to said chambers, an integral extended projection on each of said elements positioned outboard of said loading means protuberances and engaging one of said pistons to thereby generate moments about said protuberances through said projections such that the outer extremities of said first and second elements are maintained in continuous sealing engagement with the periphery of said gear teeth.

9. A gear pump, as defined in claim 8, wherein said movable sealing means is continuously urged by spring means toward said gears for peripheral sealing engagement therewith.

10. A gear pump, as defined in claim 9, wherein discharge pressure urges the pivotable protuberances of said loading means into pivotable engagement with said first and second elements to produce a line contact high pressure fluid seal between said pivot protuberances and the engaging surfaces of said first and second elements, and concurrently generate first and second vectored forces continuously positioned in substantial proximity to the respective axes of rotations of said gears.

11. A gear pump comprising a housing having a bore and means providing a closure for each end of said housing, a driver gear and a driven gear, each of said gears having an axis of rotation, said gears disposed in said bore and journaled in said housing such that said axes of rotation are parallel, a plane of symmetry located intermediate and equidistant said axes of rotation and positioned transverse a plane containing said axes of rotation, said gears having an intermesh intermediate said axis of rotation, an inlet on one side of said intermesh and an outlet on the opposite side of said intermesh, movable peripheral sealing means positioned adjacent said outlet, at least one pressure loaded sideplate urged into engagement with the lateral surfaces of said gears and said movable peripheral sealing means to sealingly enclose a high pressure discharge chamber, said movable sealing means having a first pivotable element including an arcuate surface engaging the periphery of said driver gear and a recess opposite said arcuate surface, a second pivotable element including an arcuate surface engaging the periphery of said driven gear and a recess opposite said arcuate surface, loading means having a spaced apart elongated pivot and loading protuberance positioned on each side of said plane of symmetry engaging abutting surfaces of said recesses in said first and second pivotable members, said loading protuberances responsive to discharge pressure coacting with said engaging abutting surfaces such that first moment are formed through said loading protuberances about said pivots, first and second cavities located in said loading means and positioned on each side of said plane of symmetry, resilient means received by each cavity and engaging the abutting surfaces of each of said adjacent recesses to thereby generate second moments about said pivots through said abutting surfaces such that the outer extremities of said first and second elements are maintained in continuous sealing engagement with the periphery of said gear teeth.

12. A gear pump, as described in claim 11, wherein said pivotable sealing means is urged by first spring means toward said gears, and said resilient means received by said first and second cavities are springs, all of said springs continuously urging said first and second elements toward said gears for peripheral sealing engagement therewith.

13. A gear pump, as defined in claim 12, wherein discharge pressure urges the pivotable protuberances of said loading means into pivotable engagement with said first and second elements to produce a line contact high pressure fiuid seal between said pivot protuberances and the engaging surfaces of said first and second elements, and concurrently generate first and second vectored forces continuously positioned in substantial proximity to the respective axes of rotations of said gears.

14. A gear pump comprising a housing having a bore and means providing a closure for each end of said housing, a driver gear and a driven gear, each of said gears having an axis of rotation, said gears disposed in said bore and journaled in said housing such that said axes of rotation are parallel, a plane of symmetry located intermediate and equidistant said axes of rotation and positioned transverse a plane containing said axes of rotation, said gears having an intermesh intermediate said axis of rotation, an inlet on one side of said intermesh and an outlet on the opposite side of said intermesh, movable peripheral sealing means positioned adjacent said outlet, at least one pressure loaded sideplate urged into engagement with the lateral surfaces of said gears and said movable peripheral sealing means to sealingly enclose a high pressure discharge chamber, said movable sealing means hav ing a first pivotable element engaging the periphery of said driver gear, a second pivotable element engaging the periphery of said driven gear, said first and second elements each having a recess opposite said peripheral engaging surfaces, loading means having a elongated pivot and a spaced apart spherical loading protuberance positioned on each side of said plane of symmetry engaging abutting surfaces of said recesses in said first and second pivotable members, said spherical loading protuberances responsive to discharge pressure coacting with said engaging abutting surfaces to form first and second moments about said pivots through said spherical protuberances, said loading means having a cavity positioned on each side of said plane of symmetry, resilient means received by each cavity and engaging the respective abutting surface of said recesses to thereby generate third and fourth moments about said pivots through said respective abutting surfaces such that the outer extremities of said first and second elements are maintained in continuous sealing engagement with the periphery of said gear teeth.

15. A gear pump, as described in claim 14, wherein said pivotable sealing means is urged by first spring means toward said gears, and said resilient means received by said first and second cavities are springs, all of said springs continuously urging said first and second elements toward said gears for peripheral sealing engagement therewith.

16. A gear pump, as defined in claim 15, wherein discharge pressure urges the pivotable protuberances of said loading means into pivotable engagement with said first and second elements to produce a line contact high pressure fluid seal between said pivot protuberances and the engaging surfaces of said first and second elements, and concurrently generate first and second vectored forces continuously positioned in substantial proximity to the respective axes of rotations of said gears.

References Cited UNITED STATES PATENTS 89,268 4/1869 Andrew 103126 164,147 6/1875 Conver 103126 171,651 1/1876 Crocker 103126 1,118,533 11/1914 Crocker 103-126 2,697,987 12/1954 Barclay 103-126 2,742,862 4/1956 Banker 103126 2,996,999 8/1961 Trautman l03126 3,208,393 9/1965 Kosch 103126 DONLEY J. STOCKING, Primary Examiner.

W. J. GOODLIN, Assistant Examiner.

US, Cl. X.R. 103-216 

